#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<math.h>
int main() {
	int n = 0;
	scanf("%d", &n);
	int sum = 0;
	for (int i = (n-1) * n + 1; i < pow(n, 3); i += 2) {
		sum += i;
		if (sum == (int)pow(n, 3)) {
			for (int j = (n - 1) * n+1; j<=i; j+=2) {
				printf("%d", j);
				if (j != i) {
					printf("+");
				}
			}
		}
	}
	return 0;
}